Figure 8.

Schematic diagram of increased S16 phosphorylation and nuclear accumulation of mutant htt. In the cytoplasm, full-length mutant htt is proteolytically degraded into small N-terminal htt fragments, which can enter the nucleus. Increased phosphorylation of S16 in N-terminal mutant htt enhances its aggregation and reduces its association with the nuclear pore complex protein Tpr, resulting in the accumulation of mutant htt in the nucleus. The size of N-terminal htt does not represent its actual proportion of full-length htt.